Digital pen



FIG. 1 is a perspective view of a digital pen with lid;

FIG. 2 is a front elevational view thereof;

FIG. 3 is a left side elevational view thereof;

FIG. 4 is a top plan view thereof;

FIG. 5 is a rear elevational view thereof;

FIG. 6 is a right side elevational view thereof; and,

FIG. 7 is a bottom plan view thereof.

The broken line showing of portions of the digital pen in FIGS. 1,3,4,6 and 7 is included for the purpose of illustrating environment and forms no part of the claimed design. 

The ornamental design for a digital pen, as shown and described. 